import java.net.HttpURLConnection;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
/**
 * Created by yan_my on 2017/1/14.
 */
public class Download {
    public static void  downLoadFromUrl(String urlStr,String savePath) throws IOException{
        URL url = new URL(urlStr);
        HttpURLConnection con = (HttpURLConnection)url.openConnection();
        //设置超时间为3秒
        con.setConnectTimeout(3*1000);
        //防止屏蔽程序抓取而返回403错误
        con.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
        //得到输入流
        InputStream inputStream = con.getInputStream();
        //获取自己数组
        byte[] getData = readInputStream(inputStream);
        //文件保存位置
        File saveDir = new File(savePath);
        if(!saveDir.exists()){
            saveDir.mkdir();
        }
        File file = new File(saveDir+File.separator);
        FileOutputStream fos = new FileOutputStream(file);
        fos.write(getData);
        if(fos!=null){
            fos.close();
        }
        if(inputStream!=null){
            inputStream.close();
        }
        System.out.println("info:"+url+" download success");

    }
    public static  byte[] readInputStream(InputStream inputStream) throws IOException {
        byte[] buffer = new byte[1024];
        int len = 0;
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        while((len = inputStream.read(buffer)) != -1) {
            bos.write(buffer, 0, len);
        }
        bos.close();
        return bos.toByteArray();
    }
    //用作测试
    public static void main(String[] args)
    {
        try{
            Download.downLoadFromUrl("http://www.bilibilijj.com/video/av6524351","G:\\homework_5");
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}
